Fuming Kris Boyd insists Reo Hatate's Celtic opener should have been ruled out.
Ange Postecoglou's side ran riot in the first half and got off to a blistering start when the Japanese midfielder netted in the opening exchanges.
And he reckons Bobby Madden considered blowing up.
But the pundit told Sky Sports that the goal should not have stood after Calvin Bassey was involved in a clash of heads.
Hatate would go on to add a second before Liel Abada netted the third.
At the break Boyd said: "It should have been stopped.
"I'm not just saying that, and Celtic have been by far the better team, there is no complaints about that, but that should be stopped.
"I think if you see right at the end there Bobby Madden goes to put the whistle to his mouth then stops.
"For me it's a head knock in the box and had to be stopped.
"But Rangers have been abysmal in the first half. It's 3-0 but it could have been five or six."
